phase I trial
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phase I trial, phase 1 trial
A clinical trial to determine the toxicity of a new drug. Such trials test safety and maximum dosage, help researchers discover the best way to administer a treatment (orally or intravenously) and the most appropriate dosage. Phase I trials also help to discover potentially harmful adverse effects of a new treatment. Even though the trial is not designed to show whether the treatment is effective, since an experimental drug is chosen for its promise, the patient may still benefit. Only a small number of patients are included (15 to 25 who have not been helped by other treatments), and there usually is no control group.
See also: trial